Metal working machine



Nov. 3, 1964 T. s. CRISPIN 3,15 ,9

METAL WORKING MACHINE Filed June 7, 1957 10 Sheets-Sheet 1 Nov. 3, 1964'r. s. CRISPIN. 4,

' METAL WORKING MACHINE Filed June 7, 1957 10 h s-Sheet 2 IN VEN TOR.

7344762 5 CF/sP/A I Z3- BY 'Armzzvs/ Nov. 3, 1964 1'. s. CRISPIN METALWORKING MACHINE Y 10 Sheets-Sheet 3 Filed June 7, 1957 INVENTOR.

10 Sheets-Sheet 6 INVENTOR.

Nov. 3, 1964 T. s. CRlSPlN METAL WORKING MACHINE Filed June 7, 1957 Nov.3, 1964 T. s. CRISPIN 3,154,979

METAL WORKING MACHINE Filed June 7, 1957 10 Sheets-Sheet '7 INVENTOR.

dr ve/v45 Nov. 3, 1964 T. s. CRISPIN 7 IN V E R rm 5 Case/N T. 5.CRISPIN METAL WORKING MACHINE Nov. 3, 1964 10 Sheets-Sheet 9 Filed June7, 1957 INVENTOR. Anne 5. (k/SPl/V Nov. 3, 1964 T. s. CRISPIN METALwoaxme MACHINE l0 Sheets-Sheet 10 Filed June 7, 1957 INVENTOR. 77'Hfij6e/sP/A/ EEi 2 United States Patent 3,154,??? METAL WORKUQG MAQI ThayerS. Crispin, Malibu, Cahf, assignor to Douglas Aircrfit Company, Inc.,Santa Monica, alif. Filed June 7, 1957, Ser. No. 664,432 4 Claims. (Cl.78- 39) This invention relates to machines which are adaptable forriveting, drilling, dimpling, countersinking and like operations eithersingularly or in various combinations and more particularly to anassembly of this class which is capable of functioning satisfactorilyunder relatively high operating loads and which can be utilizedeffectively in conjunction with workpieces of relatively large expanseor size.

The machine of the present invention comprises in general an assemblywherein the mechanism effecting a given operation is carried by arelatively light yoke memher which can be manually positionedaccurately, and wherein the yoke is carried by a relatively heavy membercapable of withstanding high working loads.

Progress in industry, and particularly in the aviation industry, creatinnew designs and innovations in structures, has caused the manufacturingagencies to seek faster and more eilicient fastening machines andmethods to facilitate the production of quality components at reducedcoast. There are, however, rigid specifications, and this is especiallytrue in the aircraft industry, which dictate the basic rules for thedesign of new machines, fasteners and processes, in order to meet therequirements of the engineering design and the customer. The trend forthe past several years has been toward the use of multicycling devicesutilizing available machines controlled by electronic mechanisms andprogrammed tape, and such devices have achieved the first step towardproducing a quality article with consistent results.

As aircraft design requirements changed from thin skins and stringers toheavier plate skins and extruded or milled stringers, new fasteners werespecified for securing these components into a completely sealedintegral portion of a Wing to produce what is commonly termed anintegral fuel tank. The introduction of the Slug fastener (anon-pre-headed rivet), placed in a pro-drilled and countersunk hole,upset at both ends and shaved in one position stop was a greatadvancement in machine riveting. Recently, however, heavier,high-performance transport airplanes have presented a particularchallenge, for structures havin hi her loads and stresses must be madecompatible with integral fuel tanks. These tanks are common on moderntransport aircraft and such structures must be produced with leakproofriveted joints, conforming to rigid and exacting requirements.

Modern large airplane designs call for panels which are in someinstances ten feet by fifty feet, fabricated from /4. inch thickaluminum skins fastened to stringers and having approximately 8500fasteners, all of which must be of pert" ct quality. Various machinesand methods have heretofore been used to perform operations such asriveting, drilling, countersinking, dimpling and the like. In the caseof workpieces of relatively small size, and of operations not requiringhigh operating loads and pressures, the equipment previously utilizedhas proven adequate. However, in the case of the fabrication of argeworkpieces such as wing skins, fuselage panels and spar assemblies,presently used machines and methods are inadequate. The large, heavysections of material are extremely difficult to handle and the throatdepths of present open throat yokes are not capable of handling skins orpanels of extreme width.

For the sake of convenience, the riveting operation will be consideredthe typical use of the present invention. However, as previouslydescribed, it should be understood that any of the operations normallyconcerned with the fastening of materials together can be utilized inconjunction with the present assembly.

Gne system currently in operation utilizes stationary open throat yokemachines of various types all requiring the work to be carried rivet byrivet through the machines. This, of course, necessitates a settingaside of floor space totaling at least twice that of the material beingworked on, for the work is positioned on one side of the machine andthen moved through the machine during the operating cycle to assume asimilar position on the opposite side. This utilization of extensivepremium assembly floor space is a major disadvantage inherent in suchoperating techniques and was a contributing cause of the researchleading to the present invention.

The previous approach to the problem also requires massive stationarymachines in order to overcome the problem of deflection in deep throatedyokes because of the squeezing pressures and large work-pieces involvedin present day operations. Another undesirable characteristic inherentin the current system is the difiicult problem of moving large heavyassemblies accurately through a stationary machine as each single orplural operation sequence is performed. This problem of moving the massof the Work, plus the workholder, accurately a predetermined linearincrement has brought about the development of automatically controlledmachines. These machines utilize complicated and expensive positioningequipment to index each stop position and operation, such equipmentusually entailing considerable maintenance trouble and expense.

One known installation employs a multicycling machine with handlingequipment which must move, stop and position accurately over 7 /2 tonsof components throughout the entire sequence. The weight is caused bythe necessity of moving the material to be worked upon, the work-tablecarrying the material, holding fixtures, and various related equipment.

A machine has also been heretofore proposed which would permit theworkpiece to remain stationary while the machine moved relative to theworkpiece. Rather than eliminating the existing deficiencies, thesuggestion introduces additional problems, for in such an arrangemerit apiece of equipment, weighing more than the workpiece, worktable, andvarious holding fixtures and related equipment, must be positionedaccurately rivet by rivet.

The present invention eliminates the necessity of moving the mass of themachine or the mass of the workpiece rivet by rivet, accurately. Theproblem of yoke deflection has also been eliminated by separating theriveting mechanism from the load-carrying members. By eliminating thenecessity of moving the work to the machine and by allowing the mainbody of the machine to be moved approximately in position to theworkpiece, the problem of excess utilization of premium floor space hasbeen alleviated.

The present invention is essentially a fabricator and is an improvementin the approach used to mount and operate various workingmechanisms'such as riveting equipment, dimpling equipment and morecomplicated full-cycling equipment used in drill-countersinking, rivetinserting, bucking, and shaving. It is a large tooling fimure designedto be easily positioned to the work for the general purpose ofcompleting the fastening process of drilling, riveting and shaving infabricating large aircraft wing skins, fuselage panels, and sparassemblies.

The machine comprises a generally rectangular, relatively heavy, outerframe, capable of withstanding high working stresses, and a relativelylight C-shaped yoke carried by the outer frame and movable with respectto it. Mobility of the machine is provided by supporting Y the outer.frame on non-swivel casters connected to suit-.

3 able driving means controlled by the operator. The tooling mechanismneeded to perform a given fastening operation is mounted on the yokewhich is provided with a pressure pad and a pressure foot to transmitworking loads directly to the outer frame.

To use the machine, the outer frame is first positioned adjacent aselected work area by the operator. The tooling yoke, carried by theouter frame, is then accurately positioned for a single or pluraloperational sequence within that area. Mounting the working mechanism onthe light weight yoke greatly minimizes the inertia problem of indexinga large mass a linear increment. The outer frame takes damping andriveting thrusts and is capable of being stressed in excess of ten tons.Deflection between upper and lower tooling is virtually eliminated as afactor in quality control.

Additional design advantages include the ability of the machine tofabricate a scatter pattern, including curved or angled stringers andaccess openings. By adding a sensing ring and leveling jacks, contouredpanels, including fuselage assemblies, can be fabricated to closetolerances.

On long flat panels and spar assemblies, several units can operatesimultaneously. Extra yokes can be tooled for specific requirements, andswitched in a few minutes to minimize production down-time for toolingchanges and maintenance. Installation is simple and inexpensive with nosub-floor work necessary. Relocation of the equipment is unique'for itcan be accomplished by driving the unit to a new location under its ownpower.

Yoke location is accomplished manually to plus or minus .010 inch, usingconventional methods to establish hole positions. Normally a cycle isautomatic, except for relocating, which is approximately 10% of theoperating cycle although automatic control of yoke and outer frame ispossible, thus making the entire operation completely automatic.

Other features and advantages of the present invention will be apparentfrom the following description taken in connection with the accompanyingdrawings in which:

FIGURE 1 is a perspective view of the machine of the present inventionwith portions broken away to more clearly illustrate certain details;

FIGURE 2 is schematic showing of the air motor and screw jacks,respectively, used to raise and lower the entire machine placed in theirproper positions in the lower bed support and end beams, respectively,of the outer frame member;

FIGURE 3 is a fragmentary elevation view partly in section showing thedetails of one of the screw jacks of FIGURE 2 positioned in an end beam;

FIGURE 4 is a detail fragmentary sectional elevation view showing aportion of the driving mechanism of the machine of FIGURE 1;

FEGURE 5 is a detail fragmentary sectional view taken along the line 55of FIGURE 1 showing the mounting assemblies for the yoke within theouter frame;

FIGURE 6 is an enlarged fragmentary elevation view showing in greaterdetail the tooling mechanism mounted on the machine of FlGURE 1;

FIGURE 7 is a schematic showing of the air and hydraulic circuits usedto actuate the tooling accessories shown in FIGURE 6;

FIGURE 8 is a view similar to FIGURE 6 showing an alternative toolingmechanism which can be mounted on the machine of FIGURE 1;

FIGURE 9 is a view similar to FIGURES 6 and 8 showing another toolingmechanism which can be utilized in conjunction with the machine ofFIGURE 1;

FIGURE 10 is a perspective view of a modified form of the machine of thepresent invention;

FIGURE 11 is a perspective view of the machine of the present inventionwith a workpiece positioned in the throat of the yoke;

FIGURES 12 to 14 are perspective views showing how the yoke of theembodiment shown in FIGURE 10 can be changed from one side of the outerframe to the other.

FIGURE 15 is a fragmentary perspective view of the machine of thepresent invention showing the procedure and equipment used to remove orinstall the yoke.

One embodiment of the machine of the present invention, referring now tothe drawings and more particularly to FIGURE 1 thereof, consists of astressed frame housing 12 containing a non-stressed, lightweight yoke13. The outer frame 12 is constructed as a monocoque structureconsisting of two end beams 14 and 15, respectively, to which areattached by welding or other suitable fastening means two pairs of endposts 17, 18 and 19, 20, respectively. Supported on end beams 14 and 15and positioned between and suitably fastened to each pair, respectively,of end posts 17, 18 and 19, 20 is lower bed support 22. Upper bedsupport 23 is placed in spaced apart parallel relationship with lowerbed support 22 and is also suitably attached to end posts 17, 18 and 1%,2%), respectively. The outer frame assembly 12 must be capable of givingmaximum rigidity and support for all fastening operations against aworking load in excess of 20,000 pounds. To increase stability of theexternal frame member 12, four box gussets, each designated by thenumeral 24, are afiixed to the end beams and the end posts atappropriate points.

As illustrated more clearly in FIGURE 5, secured by welding or otherwisesuitably fastened to top face 25 of lower bed support 22, are liveelongate strips, each designated by the numeral 27, preferably of hotrolled mild steel, extending the full length of the face 25. If welded,the connection need not be continuous so long as each strip 2'7 is madesecure. Five similar strips, each designated by the numeral 28, are alsosecurely attached to the bottom face 29 of upper bed support 23.

As shown in both FIGURES 1 and 5, upper and lower bed plates 32 and 33,respectively, preferably of hardened steel plate to prevent Brinelling,are attached to the elongate strips 27 and 28, respectively, by socketheaded cap screws 34.

Referring again particularly to FIGURE 1, it will be seen that outerframe 12 is carried on a three point support consisting of two heavyduty, non-swivel, grooved casters, each designated by the numeral 35,and a third caster 37, similar except for the absence of grooving. TwoOutriggers, each designated by the numeral 38, are placed at oppositeends of end beam 15 adjacent the caster 37 to prevent any twist in theframe. The entire unit is mounted upon tracks consisting of two elongatesteel plates 39 and 4t) fastened throughout their lengths to studs 42embedded in cement grouting 43. One track may be substantially flat or,as shown on 44, may contain a center depression to assure stability ofthe unit. To accommodate grooved casters 35, an inverted angle iron 45is shown tack welded at approximately six inch intervals to steel plate46.

To allow for work level adjustment vertical movement of the entiremachine is necessary. This is provided, referring now to FIGURE 2, bytwo screw jacks, each designated by the numeral 47, properly connectedto the two grooved supporting casters 35 and a third'screw jack 4%connected to non-grooved supporting caster 37. As shown more clearly inFIGURE 3, the casters are suitably attached at 49 to jack guide 5% whichin turn is connected to the lower extremity 52 of one of the screw jacks47. The power source, referring now to FIGURE 2, which actuates thejacks consists of an air motor schematically shown at 53 positioned inlower bed support 22 and connected directly to jack 4% and to jacks 47through miter gear box 54. To prevent possible rocking or twisting ofthe outer frame all three jacks are connected to the same power source.7

The two Outriggers 38, referring now to FIGURE 1,

are held in firm contact with'rail 39 by air cylinders 55,

55 connected to line pressure. When the screw jacks are actuated forraising or lowering the outer frame, the air cylinders permit theoutrigger casters 38 to extend or retract accordingly. It should beunderstood that the three main supports for the outer frame are thecasters 35, and 37 and the addition of the outriggers 38, 38 is toincrease the stability of the machine. The cylinders 55, in addition topermitting vertical adjustment, maintain the outriggers at all times infirm contact with the rail 39 regardless of the particular height atwhich the machine is set.

Referring now particularly to FIGURES 1, 2 and 4, the entire unit ispropelled by a second air motor 57, positioned in lower bed support 22,transferring power to friction-drive wheels 58, 58 through a commonshaft 59. Wheels 53, 58 drive against the rails 39 and 40, respectively,each wheel being mounted within a drive wheel frame 61 and connected bya chain and sprocket drive 62 to the drive motor 57. Two air cylinders,each designated by the numeral 63, one connected to each of the twowheel frames 69, are provided to compensate for vertical movement of theentire assembly. The traversing speed of the machine is adjustable up tothirty feet a minute in either direction, and is controlled by left andright hand buttons 64 located at the end of extension line 65 connectedto upper bed support 23 at 67. Control buttons 68, also connected to theupper bed support 23, through the extension line 71, are provided toactuate the screw jacks to raise or lower the entire assembly when worklevel adjustment is desired.

The top beam 23 of the outer frame 12 contains a large reservoir 69 forstorage of air and includes a check valve 70 to prevent unloading of thetank 69 in case of input line failure. As the chief external source ofpower to the unit is air pressure, the reservoir insures constantperformance if plant pressure should fluctuate.

Referring now to FIGURES 1 and 5, operator carriage frames 72 and 73,respectively, are suspended in guide tracks 74 and 75, respectively,attached to opposite outside faces 77 and 78, respectively, of upper bedsupport 23. Frames 72 and 73 can be constructed of any suitable materialalthough applicant presently prefers seamless steel tubing. Eachcarriage frame is provided with rollers 79, riding in the appropriateguide track to form a trolley assembly thus permitting the carriages 72and 73 to be easily moved to any point along the upper bed support 23.Each carriage frame is constructed with a base platform 80 and isadjustable in a vertical direction by means of the pin and holeconnections 82. To support the operator a scaffold 83 is suspendedbetween the two base plates 80.

Positioned within the outer housing 12, referring now to FIGURES 1, 5and 6, is the unitary C-shaped frame 13 with an upper arm 85 and a lowerarm 87 defining a work receiving throat 88. The yoke or inner framemember 13 is preferably made of such light weight metal as aluminum andis held within the outer frame 12 by upper and lower mounting assemblies89 and 90, respectively, so as to permit rotational and longitudinalmotion of the yoke within the outer frame 12. The bottom assembly 94consists of a swivel plate 92 to which the inner frame or yoke 13 isattached by means of two support brackets 93. A combination radialthrust bearing 94 is retained by the swivel plate 92 acting inconjunction with the main plate 95 which is provided with rollers 97facilitating longitudinal movement of the yoke 13 relative to bed plate33. Side retainers 99, preferably rollers, are provided to prevent themain plate from moving laterally.

A swivel pivot post 1.02 holds the two plate members 92 and together. I

The upper mounting assembly 89 is similar to lower mounting assembly 9%.Yoke 13 is attached by two support brackets 1t4 to upper swivel plate195 which, cooperating With the upper main plate 106, defines a racewayfor radial thrust bearing 167. Upper swivel pivot 6 post 108 preventsdisengagement of plate members and 166. Main rollers 1119, and sideretainers 110, respectively, are again provided to permit longitudinal,and to prevent lateral, motion, respectively, of the main plate 106 andyoke assembly 13 relative to upper bed plate 32.

The mechanism installed on the embodiment of FIG- URE lis shown indetail in FIGURE 6 and consists of a squeeze vibrator with a shavingunit which follows immediately after the rivet is upset. Other fullcycle attachments capable of installation on the basic machine aredepicted in FIGURES 8 and 9 and will be more fully discussedhereinafter.

Referring now to FIGURE 6, work receiving throat 88 of yoke 13 isbounded on opposite sides by upper and lower ram assemblies 112 and 113,respectively, attached to upper and lower arms 85 and 87, respectively.The lower assembly 113 comprises a rivet set 114 mounted on piston 115which in turn contains a rivet gun 117 capable of vertical reciprocatorymovement. The piston 115 is slidably retained within a cylinder block,not shown, which is mounted within the lower arm 87 of the yoke. Thepiston 115 is capable of vertical movement within the block and is shownin FIGURE 6 in partially extended position. Since the rivet gun 117 maybe any of the well-known makes of pneumatic vibrators, such as the ClecoG. B. Rivet Gun made by the Cleveland Pneumatic Tool Company, it is notshown here in detail and will not be described in detail.

Pivotally attached at 119 to the lower arm 87 of the yoke 13 is theshaver assembly 120. The upper portion of the assembly 120 comprises acutter mounted upon the upper end of piston 84 slidably mounted inhousing 122. Surrounding the cutter is a standard rivet shaver skirt123.

Attached to upper arm 85 is control handle 124 containing controlbuttons 125. For the purposes of using the mechanism shown in FIGURES 1and 6, three buttons marked start top, start bottom, and return top areprovided. Their operation will be more fully described hereinafter. Acylinder block, not shown, is mounted within upper arm 85 and contains aslidably movable piston 128 to which is attached anvil 129. Workingloads are transmitted to the outer frame member 12 by means of pressurepad 130 and pressure foot 132 attached to upper and lower arms 85 and87, respectively. An air cylinder 133 is secured to mounting plate 134and is provided at one end with a plate and lock slide 135.

Referring now to FIGURES 6 and 7, when the button on the control handle124 marked start top is pushed it operates bleeder valve 138 actuating aflow of air from manifold 139 through four Way valve 140 moving anvil129 into working position on top of the rivet. When the line pressureset by regulator 142 returns to normal after positioning anvil 129sequence valve 143 is opened allowing air to flow to air cylinder 133moving slide lock 135 into engagement with a recess provided in piston128 and locking anvil 12-? in position for riveting. At the same timevalve 144 is opened by line pressure which allows four way valve 145 tobe actuated by bleeder valve 147. Valve 144 acts as a safety valve toprevent the bottom assembly 113 from being operated until the anvil 129is in working position and locked.

The button marked start bottom on the control handle 124 is then pushed,operating bleeder valve 147 actuating a flow of air from manifold 139through four way valve 145 into the top of reservoir 137 forcing the oilin the reservoir to push rivet set 114 into position under the workpanel. When line pressure returns to normal, set by regulator 14.3,after positioning rivet set 114, sequence valve 14.9 is openedpermitting air to flow to booster 156 which increases line pressure tothe proper clamping pressure. When the line pressure reaches the '7 Vproper clamping pressure, pressure switch 152 opens bleeder valve-1'71thereby opening three way valve 153 permitting air from manifold 139 tolift rivet gun 117 into position and vibrate it. Pressure switch 152also opens bleeder valve 154- which actuates a flow of air throughregulator 155 through four way valve 157 to the riveting timer 158.Timer 158 by opening bleeder valve 176 actuates four way valve 145 whichforces air into the top of reservoir 159, re-positioning rivet set 114in down position. Riveting timer 158 also actuates four way valve 164 byopening bleeder valve 131. Two three way valves 162 and 163,respectively, are also actuated when the timer opens bleeder valves 232and 233, respectively. When rivet set 114 returns to the down positionit opens two way valve 169 allowing air to flow through four way valve156 to air cylinder 170 which moves shaver unit 120 into positionbeneath the upset rivet. The air motor actuating the cutting blades isset in operation through line 172. When shaver unit 120 is positionedunder the rivet it opens three way valve 173 permitting air to push oilin reservoir 174 into the bottom of shaver unit 120 feeding the cuttingblades into the upset rivet and shaving it flush with the skin. Valve162 starts operation of shaver timer 164 which at the end of a timedstroke opens three bleeder valves 165, 167, and 168. These bleedervalves reverse the how of air through four way valves 14%, 160 and 157.When four way valve 14% is actuated by bleeder valve 165 aftercompletion of the shaving operation the flow of air to air cylinder 133is reversed retracting it and lifting anvil 129 into the up position. Ifit is desired the button marked return top can be pushed actuating fourway valve 140 to retract air cylinder 133 and lift anvil 129 into the upposition thus interrupting the automatic cycle. The emergency stopbutton also located on control handle 124 will return the upper ram,lower ram and shaver to a normal position immediately at any time duringthe operation of the machine.

Referring now to FIGURE 1, a coupling plug 178 is provided to connectthe air and oil circuitry located in the yoke to a source of airpressure. This plug is a quick disconnect and facilitates theinterchange of yokes by providing a single connection for line 179 whichcan be made and broken when an interchange is desired.

Referring now to FIGURE 15 consideration has been given to the vitalproblem of down-time which so frequently upsets manufacturing schedules.The present invention has been designed in such a manner that theworking yoke 13 can be readily removed from the outer frame 12 by simplybreaking the quick disconnect plug 178 and air line 179 just discussedand rolling the yoke onto dolly 186. A standby yoke can be rolled intoplace and made operative by re-attaching line 179. This feature willalso allow yokes carrying different working mechanisms to be readilyinstalled between the beams of the outer frame 12.

In FIGURE 8 there is shown an additional embodiment which can beutilized in conjunction with the basic machine. The tooling necessary todrill and countersink the hole, insert the rivet, vibrate or squeeze therivet, and shave the rivet is mounted in a three station turret 182which in turn is attached to the lower portion 183 of the yoke 184. Thedesign of the turret is such that any one of the three stations can beused manually, or in sequence, as an automatic operation.

In the embodiment of the invention presently being described, the lowerpressure foot 185 is first brought up by the action of pneumaticactuator 187 to contact the bottom of the skin not shown. The upper ram188 is then lowered, causing upper pressure foot 189 to exert clarnp ingpressure on the parts being fastened. The work is.

held at a predetermined pressure throughout the complete cycle, thuseliminating burrs or chips, and at the same time keeping positive holealignment for rivet insertion which is critical for fuel-tight riveting.

The drill and countersink cutter 1% is then moved up to perform thedrill and countersink operation. Applicant is presently using a positivescrew feed air drill with an out feed adjustment from 0 to A of an inch.The positive screw feed provides constant size of chip, close hole sizecontrol and less chance for rifting of the hole. The drill andcountersink cutter 190 then retracts and the mechanism is rotated 128degrees by pneumatic actuator 192.

The feeding of slug or headed rivets is accomplished through use of therivet feed mechanism 1%. In operation the arm 194 swings to and from arivet magazine according to known practice, the rivet falling into thehole 195 provided in the upper pressure foot 189. Bucking bar 197 pushesthe rivet firmly through the hole and remains in contact While rivet gun198 advances, performs the riveting operation, and retracts, and theturret then rotates The rivet shaver 199 then advances and the cuttershaves the rivet flush with the skin. The bucking bar 19'? and ram 188retract after the shaver has retracted and the turret then returns toits initial position. The lower pressure foot drops clear of the skin.The yoke 184 is moved to the next position and the above operations arerepeated.

Positive indexing of turret 132 is controlled by a shot pin stop, notshown, at 120 intervals. Timing of each station is adjustable by use oftimers, not shown, adjustable from 0 to '15 seconds in one-quartersecond increments. The timers can be mounted on top of the yoke withineasy reach of the operator.

Controls for semi-automatic or full automatic operation are mounted onthe control handle 200 fastened to upper part 201 of the yoke 134 withinfinger reach of the operator. Controls include everything for single ormultiple operations with an emergency button which will cut olf power atany point in the automatic cycle.

In the embodiment of the invention shown in FIGURE 9 there is also shownan automatic sequence operating mechanism consisting of a three stationturret 202. Here, however, the axis of rotation of the turret ishorizontal rather than vertical as shown in the embodiment of FIG- URE8. The operation is identical however except for the plane of rotation,the spindle 203 having mounted thereon a drill and countersink cutter204, a rivet gun 205, and a rivet shaver 296.

The embodiment of the invention shown in FIGURE 10 utilizes a broken armyoke support in place of the sliding yoke arrangement of FIGURE 1previously described in detail.

The outer frame 207 is again designed as a monocoque structure. However,the two pairs of end posts have been replaced by single members 2&8 and2%. Attached by welding, or other suitable fastening means, to theopposing inside faces of upper and lower bed supports 244 and 245,respectively, are upper and lower thrust plates 247 and 248,respectively. The yoke supporting mechanism consists of two arms orhinges, a primary hinge 210 attached at one end to the outer frame 207and joined at the opposite end to a secondary hinge 211 which in turn isconnected to the yoke 212. The primary hinge 210 is attached to theouter frame 207 by means of hinge pins 213 rotatably mounted withinhinge pin brackets 214. Similar hinge pin connections 215 are also usedto connect the secondary hinge 211 to the primary hinge 210. The yoke isprovided with pressure pad 218 and pressure foot 219 to transfer thesqueezing pressure to the outer frame 207.

With the double arm arrangement, it is possible to move the yoke to anyposition within the support area. The arms are mounted on radial andthrust type ball bearings, thus keeping joint friction to a minimum. Theplacement of the yoke pivot point and utilization of a two piece brokenarm arrangement allows the operator maximum freedom of control inpositioning the riveter over the work-piece. The yoke, of course, isdesigned to accommodate various types and sizes of fastening mechanismsand any of the mechanisms previously discussed can be used inconjunction with the present embodiment.

The present yoke is also preferably fabricated of aluminum alloy,thereby reducing the weight considerably and keeping operator fatigueand yoke positioning effort to a minimum. This reduction of weightpermits easier transfer of the yoke from one side of the outer frame tothe other. In the present embodiment retainers 217 are provided alongthe edges of the lower plate 248 to prevent the yoke from sliding out ofthe plate area.

Quick disconnect joints are provided where yoke 212 connects to thesecondary hinge 211. These joints are preferably fast acting mechanicalconnections which do not require starting threads or hand tools tooperate and are shown in FIGURE as comprising a pair of spring biasedtelescoping pins 249 acting in cooperation with recesses 250 provided inthe secondary hinge 211.

In some instances where the particular yoke being used is notsufficiently deep throated to permit the operator to position theriveting mechanism over the far side of the workpiece, the yoke can bedisconnected from the secondary hinge on one side of the outer frame andconnected to a similar broken arm arrangement connected to the oppositeside of the outer frame. It should be understood that such a change-overcan'be accomplished in several ways. For example, the procedurepreviously described in connection with FIGURE can be utilized totransfer the yoke shown in the embodiment of FIG- URE 10. However,FIGURES 12, 13 and 14 show a greatly simplified method of performingthis operation.

As shown, in FIGURES 12, 13 and 14, the yoke 222 is provided with tworecesses or pin sockets 223 located at the top and bottom, respectively,of the yoke at approximately the center of gravity. Attached to upperand lower bed supports 224 and 225, respectively, are brackets 227 and228, respectively, each bracket containing a spring biased telescopingpin 229.

In FIGURE 12, yoke 222 is shown attached to end post 255 of the outerframe 257 preparatory to starting the change-over operation. The yoke222 is first positioned relative to the outer frame 257 as depicted inFIG- URE 13 with the exception that the yoke, at this stage of theoperation, would still be attached to secondary hinge 258. The springbiased telescoping pins'229 are then extended into the receiving sockets223 provided in the yoke 222. At this point yoke 222 is pivotallysupported in the outer frame 257 by means of the pins and sockets 229and 223, respectively. Quick disconnect joints 259 and 269,respectively, are then released, completely freeing yoke 222 from thesecondary hinge 258. When the secondary hinge 258 has been moved back toa retracted position, the stage of the change-over operation is thatshown in FIGURE 13.

Yoke 222 is then pivoted to the position shown in FIGURE 14 andconnected to the secondary hinge 262 by inserting the spring biasedtelescoping pins 263 and 264, respectively, into receiving slots 265 and267, respectively, provided in the secondary hinge 262. Pins 229 inbrackets 227 and 228, respectively, are then retracted and the machineis ready for operation. It should be understood that, if desired, thesame set of hinges can be utilized for operation of the yoke from eitherside of the outer frame 257, thus obviating the necessity of providingtwo sets of hinges. In this event the yoke is switched carrying with itthe primary and secondary hinges 268 and 258, respectively, and quickdisconnect joints are provided where the primary hinge attaches to theouter frame.

As shown in FIGURE 1, the power connections 179 to the yoke 13 areflexible, extending from the center of the lower oed support 22 and arelong enough to follow the full movement of the yoke. shown in FIGURES12, 13 and' 14 similar power lines 3% are provided and are disconnectedbefore the com- In the change-over operation mencement of thechange-over sequence and a second set of power lines 392, extending fromthe opposite side of the lower bed support 234, are connected to theyoke when the transfer is complete. A second yoke could be added to thepresent embodiment of the invention or to the embodiment shown in FIGURE1 by utilizing both power connections at the same time. Such anarrangement obviates the necessity of switching the yoke to complete thefastening operation and permits simultaneous use of both yokes thusconsiderably reducing the time required to complete any particularfastening sequence.

The operation of the present invention is seen more clearly by referenceto FIGURE 11. The application there shown is a typical fasteningprocedure frequently encountered in the aircraft industry consisting ofa skin panel 235 being reinforced by attaching longitudinal stringers237. Again it should be made clear that the machine of the presentinvention is not limited to the operation presently being described. Thepresent invention achieves a new degree of accuracy and ease in machineportability and is adaptable for work in fastening, dimpling and otherapplications where high thrust tools are an essential part of theoperation. However, to simplify the disclosure of the operation of theinvention, it will be described herein as a machine utilizing theattachments previously described in connection with a workpiece as shownin FIGURE 11.

The detail parts 235 and 237 are first assembled by being placed on asuitable jig or fixture and secured together by some temporary fasteningmeans such as tack riveting. The assembled unit is then transported tothe work area of the machine and placed upon a supporting structure suchas that shown in FIGURE 11 at 238 and 239.

The operator poisitioned on the scaffold 83 shown in FIGURE 1 has withineasy reach the mobile control unit 64 attached to extension cord 65which is provided to control the traverse movement of the entire machinealong the rails 39 and 40. Referring still to FIGURE 1, a second mobilecontrol unit 68, attached to extension line 71, is also providedpermitting the operator toadjust the machine in a vertical direction. Byuse of the proper switch on the control unit 63 the vertical height ofthe entire machine is adjusted by actuating the air motor 53, shown inFIGURE 2, so that the workpiece is approximately at the center of thework receiving throat 240 of the yoke 242, as shown in FIGURE 11. Theselection of the proper switch on unit 64 actuates air motor 57 and themachine is moved along the rails to the selected work area of theworkpiece.

The yoke is then positioned manually by the use of control handle 243,referring now to FIGURE 11. If desired the yoke may utilize a powerassist for longitudinal travel which is adjustable to the operators feeland automatically comes into play when the control handle is pulled orpushed. It should also be understood that complete automatic control ofthe machine is possible. Such complete automatic control is notfeasible, however, unless a given machine application produces savingsin programming which are large enough to offset increased machine andmaintenance costs.

Assuming for the sake of clarification that the mechanism mounted on themachine shown in FIGURE 11 is that depicted in FIGURES l and 6, thedetails of which have been fully described previously, the operatingprocedure, when the yoke is properly positioned, is as follows. Thebutton marked start top on the control handle 12 i is pushed bringingdown the anvil 129. The button marked start bottom is then pushedadvancing the rivet set 114 and causing the pneumatic vibrator to upsetthe rivet. "As previously described in connection with FIGURE 6, the set114 retracts and the shaver is positioned and advanced, shaving theupset'head flush with the plate. u

When the mechanisms depicted in FIGURES 8 and 9 are utilized inconjunction with the basic machine, the

1 1 positioning and operation of the outer frame and yoke remain thesame. Any deviation in the overall operation occurs subsequent to thepositioning of the yoke and frame and is a result of the differingindividual tools and operational sequences which characterize each ofthe many possible yoke attachments.

If desired two yokes can be mounted in, or attached to, the sameexternal frame thus permitting a simultaneous operation on each side ofthe workpiece. However, because of the absence of yoke deflectionproblems, it is possible to utilize a deep throated yoke enabling theoperator to reach any point on the workpiece within the work area.

It will be remembered in connection with the embodiment shown in FIGUREthat, in lieu of turning the workpiece around to permit access to theentire panel width, in the case of relatively short throated yokes, itis possible to switch the yoke from one side of the outer frame to theother as previously described in connection with FIGURES 12 to 14. mentshown in FIGURE 1 this can be accomplished by simply driving the unit toa position beyond the end of the workpiece and simply reversing theposition of the yoke within the outer frame. The operator can thenproceed to fasten the opposite side of the panel to the stringers in themanner just previously described.

It will thus be seen that in all the embodiments of the invention hereinillustrated there is provided a separation of the heavy load carryingmembers from the portion of the machine carrying any given mechanism.There is thus provided a basic machine which is capable of takingfastening operations such as riveting back to the operator, thusallowing engineering changes to be readily put into effect bymanufacturing. The problem of incorporating such engineering changes andalso master changes in the aircraft industry has sharply accentuated theneed for such a machine.

Although the new preferred embodiments of the present invention havebeen shown and described herein, it is to be understood that theinvention is not to be limited thereto, for it is susceptible to changein form and detail Within the scope of the appended claims.

I claim:

1. A metal fabricating machine comprising: a heavy frame havinghorizontal upper and lower load-bearing members and spaced-apartvertical end posts at each of the ends of the members; relatively lightfabricating tool means encompassed by the frame and adapted to exerthigh working loads along a vertical axis; pressure means in alignmentwith said tool means for directly transmitting said loads to the frame;said tool means being adapted for insertion into and removal from theframe through either of the openings between the end posts.

2. A metal fabricating machine comprising: a generally rectangular,load-bearing, closed frame adapted to receive a Work piece; relativelylight fabricating tool means encompassed by the frame, said tool meansincluding clamping and riveting means adapted to exert high loads on awork piece; pressure means in axial alignment with said tool means fordirectly transmitting said loads to the frame; said frame being adaptedfor gross localizing movement of the machine along the length of thework piece and said tool means being adapted for fine transverse and Inthe case of the embodi- 12 radial movements over the work piece at anygiven localized position along the length of the work piece, whereby themachine can be precisely positioned for fastening operations on astationary work piece without simultaneous movement of the frame and thetool means.

3. A riveting machine comprising: a generally rectangular, load-bearing,closed frame; a relatively light C- shaped yoke mounted within the frameand carrying clamping and riveting tool means adapted to exert highloads on a work piece; pressure means in axial alignment with the toolmeans for transmitting said loads directly to the frame; means forpositioning the machine with respect to a stationary, generallyhorizontal work piece, said means including power-actuated driving meanson the frame for gross localizing movement of the machine along thelength of the work piece, roller and swivel means between the yoke andthe frame so constructed and arranged that the yoke may be moved bymanual operation horizontally in the plane of the frame and pivotallyabout a vertical axis, whereby the tool means can be preciselypositioned over the work piece without simultaneous movement of therelatively heavy frame.

4. A machine for fabricating contoured, elongated aircraft panels, saidmachine comprising: an upright, substantially rectangular, closed frameadapted to absorb high axial loads without material deformation; arelatively light, C-shaped yoke mounted within the frame and carryingtool means including means for clamping the panel components togetherand supporting the panel, means for riveting the panel components, andmeans for shaving the upset rivets to produce a flush surface on thepanel; said clamping and riveting tool means being adapted to exert highloads on the panel during the riveting operation; pressure means inalignment with the tool means for directly transmitting said loads tothe frame; said frame being adapted for gross localizing movement of themachine along the length of the panel and said yoke being adapted forfine transverse and radial movements over the panel at any givenlocalized position along the length of the panel, whereby the machinecan be precisely posi- 'tioned for fabricating operations on the panelwithout simultaneous movement of the yoke and the relatively heavyframe.

References Cited in the file of this patent UNITED STATES PATENTS746,521 Kagelmacher Dec. 8, 1903 748,823 Weaning Jan. 5, 1904 840,859Morse Jan. 8, 1907 1,158,874 Walker Nov. 2, 1915 1,386,629 Kern Aug. 9,1921 1,450,198 Bailey Apr. 3, 1923 1,534,018 Ames Apr. 21, 19251,739,152 Larsen Dec. 10, 1929 2,312,554 Jacques Mar. 2, 1943 2,456,125Johndrew Dec. 14, 1948 2,650,521 Steinbrecker Sept. 1, 1953 2,799,187Van Dusen July 16, 1957 2,974,548 Miller Mar. 14, 1961 FOREIGN PATENTS441,448 Germany Mar. 4, 1927

1. A METAL FABRICATING MACHINE COMPRISING: A HEAVY FRAME HAVINGHORIZONTAL UPPER AND LOWER LOAD-BEARING MEMBERS AND SPACED-APARTVERTICAL END POSTS AT EACH OF THE ENDS OF THE MEMBERS; RELATIVELY LIGHTFABRICATING TOOL MEANS ENCOMPASSED BY THE FRAME AND ADAPTED TO EXERTHIGH WORKING LOADS ALONG A VERTICAL AXIS; PRESSURE MEANS IN ALIGNMENTWITH SAID TOOL MEANS FOR DIRECTLY TRANSMITTING SAID LOADS TO THE FRAME;SAID TOOL MEANS BEING ADAPTED FOR INSERTION INTO AND REMOVAL FROM THEFRAME THROUGH EITHER OF THE OPENINGS BETWEEN THE END POSTS.